Simple startup script on instance creation on vultr.com, for this case only updating repo and adding swap.

startup script on vultr: add 2GB of SWAP

#!/bin/bash


#add swap
SWAP_SIZE="2G"
SWAP_MOUNT_NAME='/swapfile'
SWAP_EXISTS=`swapon -s`
SWAP_ON_STARTUP="$SWAP_MOUNT_NAME   swap    swap    sw  0   0"
if [[ -z $SWAP_EXISTS ]] && [[ ! -f $SWAP_MOUNT_NAME ]] ; then
 fallocate -l $SWAP_SIZE ${SWAP_MOUNT_NAME}
 echo "allocating $SWAP_SIZE on $SWAP_MOUNT_NAME"
 chmod 600 $SWAP_MOUNT_NAME
 mkswap $SWAP_MOUNT_NAME
 swapon -s
 echo $SWAP_ON_STARTUP >> /etc/fstab
fi